Espresso: A Stream Cipher for 5G Wireless Communication Systems.
Elena Dubrova, Martin Hell · 2015
Abstract. The demand for more efficient ciphers is a likely to sharpen with new generation of products and applications. Previous cipher de-signs typically focused on optimizing only one of the two parameters- hardware size or speed, for a given security level. In this paper, we present a methodology for designing a class of stream ciphers which takes into account both parameters simultaneously. We combine the ad-vantage of the Galois configuration of NLFSRs, short propagation delay, with the advantage of the Fibonacci configuration of NLFSRs, which can be analyzed formally. According to our analysis, the presented stream ci-pher Espresso is the fastest among the ciphers below 1500 GE, including Grain-128 and Trivium.